Persimmon’ll Tan Your Tonsils

Diospyros virginiana

(Dios, god, pyros, grain = divine grain, an ancient name for a tasty treat. Virginiana is self-explanatory, a great state for Persimmons and for lovers)

Ebenaceae, the Ebony Family

Fridays! Deployed for non-teaching: on a bad day meetings, on a good day botany. Today, eye doctor, delaying the fieldtrip with John until late in the day, when we found stunning red-flowered Leafless Ladies Tresses, Sacoila lanceolata. I was too doctor-blind to shoot a picture, and John needs time to process his. Will sneak it into a future blog cuz it is so dang purty. So then, in 20-20 hindsight, my Native Plants Class yesterday encountered more beautiful species at Grassy Waters Preserve near Palm Beach Gardens, Florida, than you can shake a Sacoila at.

Persimmon. All photos by John Bradford.

Blooming now in the wet mud there is Persimmon, a tree I know best from rocky hilltops in The Ozarks, and more recently as a wet friend in the swamp. The contradictory divided habitats seem odd? Species represented in swamps and also high and dry are not that rare, but that’s for another day. Persimmon tolerates diverse circumstances across much of eastern North America.

Persimmons have hundreds of species, a few to be seen or eaten in Florida, although D. virginiana is the only native. Diospyros kaki, an Asian species with many cultivated selections, is the big orange persimmon of grocery stores. Florida fruit fanciers likewise savor “Chocolate Pudding Tree” (Diospyros digyna, aka D. nigra, aka Black Sapote). Escaped at the southern tip of the state is the Malay Persimmon, D. maritima. True Ebony, Diospyros ebenum, is cultivated a teensie weensie here in Palm Beach County.

Multiple species of Diospyros are marketed as “Ebonies,” which raises the question, does our native species have dark “ebonyish” heartwood? Yes, and there’s more. The chunky bark served historically as a source of inky dark dye, and “indelible ink” reportedly can be made from the fruit juice.

Peach colored petioles.

In the absence of bark, fruit, or flower, Persimmon can be challenging to recognize, but here is a handy hint…the twigs have no buds at their tips…they just fizzle out. Good clue, and here’s more, the leaf stalk tends to be reddish or peach colored, at least when young.

Native Persimmon is one of the most delicious foods in the megaverse. I’d trade a bushel of Chocolate Pudding fruits and Publix Persimmons for a half-dozen fresh ripe native Persimmons, but good luck finding any here. Scarce they are, and the wildlife beats you out. To be totally tasty, they need a frost, although there are frostless cultivated selections. The trees are separately male or female, and they clone by root suckers, with the consequence that an entire “population” can be completely male, never making fruits.

Biting an unripe Persimmon fruit is memorable. Pucker up Buttercup! It is astringent on steroids, which explains the old-time use of the juice to relieve “piles.” Astringents still help down south, and it all has to do with tannins. Tannins are plant products with a super-power—to bind proteins. That is how tannins tan hides…they tie the proteins to each other, helping to preserve the skin presumably by rendering the proteins inaccessible to decomposers. (This to be more my presumption than scientific fact.) In your mouth, they “tan your hide” too, instantly interlinking the proteins there. That is potent protection from unwelcome nibblers. DO NOT even think about eating my fruit before it ripens! (The seeds are not yet good to go.)

The flower, magnified

But how then does the fruit go from dreadful to delightful upon ripening? Early in development the tannins collect in special cells called, yep, tannin cells. Little bags of trouble. The toxic tannins sequester safely until they cross your lips. You might think chewing breaks the nasty little bags to unleash the torment, but wrong. Back in 1906 botanists showed the tannin trigger to be saliva entering tannin cells by osmosis. No need for a biology lesson on osmosis here; suffice it to say dissolved tannins draw spit into the tannin cells to build pressure and burst the little poison balloons.

That explains the punishing pucker. But we ask again impatiently, how do the fruits become harmless abruptly when the time is right? Does the tannin go away? No. The tannins condense into harmless crunchy grains no longer having the ability to draw in water nor to bind proteins. Has Persimmon served to tan leather? Yes, although commercially there are better sources.

Right the wood is rock hard and pretty…must be enjoyed bu wood turners? Farther north you see them as nice trees. Around here I’ve never seen a large specimen with big thick trunk, but that may be mere failure to notice.